ISO 14469-3:2006

Road vehicles — Compressed natural gas (CNG) refuelling connector — Part 3: 25 MPa (250 bar) connector

ISO 14469-3:2006 applies to compressed natural gas (CNG) vehicle nozzles and receptacles constructed entirely of new, unused parts and materials. CNG fuelling connection nozzles consist of the following components, as applicable: receptacle and protective cap (mounted on vehicle); nozzle. ISO 14469-3:2006 applies to devices which have a service pressure of 250 bar and refers only to a service pressure of 250 bar. This part of ISO 14469 applies to devices with standardized mating components and applies to connectors which: prevent natural gas vehicles from being fuelled by dispenser stations with service pressures higher than that of the vehicle; allow natural gas vehicles to be fuelled by dispenser stations with service pressures equal to or lower than the vehicle fuel system service pressure. ISO 14469-3:2006 is applicable to compressed natural gas in accordance with ISO 15403.

Véhicules routiers — Connecteur de remplissage en gaz naturel comprimé (GNC) — Partie 3: Connecteur 25 MPa (250 bar)

General Information

• Status: Withdrawn
• Publication Date: 05-Jul-2006
• Withdrawal Date: 05-Jul-2006
• ICS: 43.060.40 - Fuel systems
• Technical Committee: ISO/TC 22/SC 41 - Specific aspects for gaseous fuels
• Drafting Committee: ISO/TC 22/SC 41/WG 3 - Fuel system components and refuelling connector for vehicles propelled by gaseous fuel
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 03-Jan-2017

Relations

• Revised: ISO 14469:2017 - Road vehicles — Compressed natural gas (CNG) refuelling connector
• Effective Date: 19-Oct-2013
• Consolidated By: ISO 14730:2014 - Ophthalmic optics — Contact lens care products — Antimicrobial preservative efficacy testing and guidance on determining discard date
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 14469-3
First edition
2006-07-15

Road vehicles — Compressed natural
gas (CNG) refuelling connector —
Part 3:
25 MPa (250 bar) connector
Véhicules routiers — Connecteur de remplissage en gaz naturel
comprimé (GNC) —
Partie 3: Connecteur 25 MPa (250 bar)




Reference number
ISO 14469-3:2006(E)
©
ISO 2006

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ISO 14469-3:2006(E)
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ISO 14469-3:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 General construction requirements. 2
5 Nozzles. 3
6 Standard receptacle dimensions . 4
7 Receptacles . 6
8 Instructions . 6
9 Marking . 7
10 Tests. 7
10.1 General requirements. 7
10.2 User interface. 8
10.3 Impact resistance. 8
10.4 Receptacle protective caps . 9
10.5 Leakage at room temperature . 9
10.6 Valve operating handle. 10
10.7 Abnormal loads. 10
10.8 Rocking/Twisting . 11
10.9 Mounting hardware torque . 12
10.10 Low and high temperatures. 12
10.11 Durability . 13
10.12 Hydrostatic strength. 17
10.13 Corrosion resistance. 17
10.14 Deformation. 18
10.15 Non-igniting evaluation. 18
10.16 Pressure-tight protective cap (PTPC). 18
Annex A (informative) Nozzle characteristics . 21
Annex B (informative) Manufacturing and production test plan . 22
Annex C (normative) Receptacle test fixture. 23

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ISO 14469-3:2006(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 14469-3 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 25,
Vehicles using gaseous fuels.
ISO 14469 consists of the following parts, under the general title Road vehicles — Compressed natural gas
(CNG) refuelling connector:
— Part 1: 20 MPa (200 bar) connector
— Part 2: 20 MPa (200 bar) connector Size 2
— Part 3: 25 MPa (250 bar) connector
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ISO 14469-3:2006(E)
Introduction
This part of ISO 14469 was developed for use in the examination, testing and certification of newly produced
compressed natural gas (CNG) vehicle fuelling nozzles and receptacles, and as such, applies only to the
nozzles and receptacles used in CNG fuelling systems, and not to the system itself.
A nozzle certified to this part of ISO 14469 will be functionally compatible from a safety and performance
perspective with all listed receptacles of compatible profile and system pressure. Similarly, a certified
receptacle will be functionally compatible from a safety and performance perspective with all listed nozzles of
compatible profile and system pressure.
As there may eventually be many different kinds of nozzle and receptacle available from a variety of
manufacturers which, for safety reasons, must all be compatible with one another, this part of ISO 14469
specifies a series of receptacle profiles. These standard profiles incorporate the design specifications (mating
materials, geometry and tolerances) which may be considered in the certification of a submitted nozzle or
receptacle. This part of ISO 14469 refers only to one working pressure and one application. Other working
pressures and applications are under consideration for the future.
The construction and performance of nozzles and receptacles are based on the observation that three main
parameters affect user safety and system compatibility.
a) Working pressure
All nozzles and receptacles are designed to have a working pressure of 31,5 MPa (315 bar).
b) Design life
Frequency of use is the second parameter to be considered. Since frequency of use will differ with the
nozzle/receptacle application (i.e. public sector, fleet employee and residential), all receptacles will be
tested at 10 000 connect/disconnect cycles for compliance with this part of ISO 14469. In addition, all
nozzles will be tested according to the following frequency use classifications, as applicable:
1) class A nozzle, specifying high frequency use, with a cycle life of 100 000 and equating to
approximately 100 fills per day for three years;
2) class B nozzle, specifying medium frequency use, with a cycle life of 20 000 cycles and equating to
approximately 10 fills per day for five years.
c) Training
Operator training required is in accordance with national requirements.

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INTERNATIONAL STANDARD ISO 14469-3:2006(E)

Road vehicles — Compressed natural gas (CNG) refuelling
connector —
Part 3:
25 MPa (250 bar) connector
1 Scope
1.1 This part of ISO 14469 applies to compressed natural gas (CNG) vehicle nozzles and receptacles
hereinafter referred to as devices, constructed entirely of new, unused parts and materials. CNG fuelling
connection nozzles consist of the following components, as applicable:
a) receptacle and protective cap (mounted on vehicle) (see Clause 7);
b) nozzle (see Clause 5).
1.2 This part of ISO 14469 applies to devices which have a service pressure of 250 bar, hereinafter referred
to as B250 [see 9 a) 3)].
This part of ISO 14469 refers only to a service pressure of 250 bar.
1.3 This part of ISO 14469 applies to devices with standardized mating components (see 5.8 and 7.7).
1.4 This part of ISO 14469 applies to connectors which:
1) prevent natural gas vehicles from being fuelled by dispenser stations with service pressures higher
than that of the vehicle;
2) allow natural gas vehicles to be fuelled by dispenser stations with service pressures equal to or lower
than the vehicle fuel system service pressure.
1.5 This part of ISO 14469 is applicable to compressed natural gas in accordance with ISO 15403.
1.6 All references to pressures (bar) throughout this part of ISO 14469 are to be considered gauge
pressures unless otherwise specified.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 188, Rubber, vulcanized or thermoplastic — Accelerated ageing or heat-resistance tests
ISO 1817:1985, Rubber, vulcanized — Determination of the effect of liquids
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
ISO 15403, Natural Gas — Designation of the quality of natural gas for use as a compressed fuel for vehicles
ISO 15501-1, Road vehicles — Compressed natural gas (CNG) fuel systems — Part 1: Safety requirements
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ISO 14469-3:2006(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
dry air
air with moisture content such that the dew point of the air at the required test pressure is at least 11 °C below
the ambient test temperature
3.2
hydrostatic pressure
pressure to which a component is taken to verify the structural strength of the component
3.3
working pressure
maximum pressure that a CNG refuelling connector can be expected to withstand in actual service
3.4
service pressure
settled pressure of 25 MPa (250 bar) at a uniform gas temperature of 15 °C
3.5
positive locking means
feature that requires actuation of an interlocking mechanism to allow connection/disconnection of the nozzle
from the receptacle
3.6
CNG refuelling nozzle
device that permits quick connection and disconnection of fuel supply hose to the CNG receptacle in a safe
manner, hereafter referred to as CNG nozzle
3.7
CNG refuelling receptacle
device connected to a vehicle or storage system, which receives the CNG refuelling nozzle and permits safe
transfer of fuel, hereafter referred to as receptacle
3.8
CNG refuelling connector
joined assembly of CNG nozzle and receptacle, hereafter referred to as connector
4 General construction requirements
4.1 CNG nozzles and receptacles manufactured in accordance with this part of ISO 14469 shall be
designed in accordance with reasonable concepts of safety, durability and maintainability.
4.2 CNG nozzles and receptacles shall be well fitted and manufactured in accordance with good
engineering practice. All construction requirements may be met by either the construction specified in this part
of ISO 14469 or another construction that gives at least equivalent performance.
4.3 CNG nozzles and receptacles shall be:
⎯ designed to minimize the possibility of incorrect assembly;
⎯ designed to be secure against displacement, distortion, warping or other damage;
⎯ constructed to maintain operational integrity under normal and reasonable conditions of handling and
usage.
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ISO 14469-3:2006(E)
4.4 CNG nozzles and receptacles shall be manufactured from materials suitable and compatible for use
with compressed natural gas at the pressure and the temperature ranges to which it will be subjected
(see 1.6).
The minimum temperature range shall be selected by the manufacturer between the following ranges:
− 40 °C to 85 °C
− 20 °C to 120 °C
4.5 CNG nozzles and receptacles constructed of brass shall use brass alloys with a copper mass content
u 70 %.
This ensures proper material compatibility with all the constituents of natural gas.
4.6 Separate external three-way valves shall be constructed and marked so as to indicate clearly the open,
shut and vent positions.
4.7 CNG nozzles and receptacles shall be operated to connect and disconnect without the use of tools.
4.8 The receptacle shall be mounted on the vehicle in compliance with ISO 15501-1.
4.9 Jointing components shall provide gas-tight sealing performance.
5 Nozzles
5.1 Nozzles shall be one of the three types according to a), b) and c). See also Annex A.
a) Type 1: is a nozzle for use with dispensing hoses that remain fully pressurized at dispenser shutdown.
The nozzle shall not allow gas to flow until a positive connection has been achieved. The nozzle shall be
equipped with an integral valve or valves, incorporating an operating mechanism which first stops the
supply of gas and safely vents the trapped gas before allowing disconnection of the nozzle from the
receptacle. The operating mechanism shall ensure the vent valve is in the open position before the
release mechanism can be operated and that the gas located between the nozzle shut-off valve and the
receptacle check valve is safely vented prior to nozzle disconnection (see 10.2).
b) Type 2: is a nozzle for use with dispensing hoses that remain fully pressurized at dispenser shutdown. A
separate three-way valve connected directly, or indirectly, to the inlet of the nozzle is required to safely
vent trapped gas prior to nozzle disconnection. The nozzle shall not permit the flow of gas if unconnected.
Venting is required prior to disconnection of the nozzle (see 10.2).
c) Type 3: is a nozzle for use with dispensing hoses which are automatically depressurized – 0,5 MPa
(5 bar) and below – at dispenser shutdown (see 10.2).
In addition, nozzles shall be classified in terms of cycle life as follows:
⎯ class A, specifying high frequency use, with a cycle life of 100 000;
⎯ class B, specifying low frequency use, with a cycle life of 20 000.
5.2 Venting or de-pressurization of all nozzle types is required prior to disconnection. Disconnection of all
nozzles shall be able to be accomplished in accordance with 10.2.
5.3 The method for attaching the nozzle to the fuel dispensing system hose shall not rely on the joint
threads between the male and female threads for sealing (e.g. conical threads).
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ISO 14469-3:2006(E)
5.4 The three-way valve exhaust port of Type 1 and Type 2 nozzles shall be protected from the ingress of
foreign particles and fluid which would hamper the operation of the valve.
5.5 The portions of a nozzle which are held by the user for connection or disconnection may be thermally
insulated.
5.6 A Type 1 nozzle shall bear a marking in accordance with Clause 9, indicating the direction of the open
and shut operation of the actuating mechanism, if necessary.
5.7 The interface surface of the nozzle shall be constructed of material having a hardness > 75 Rockwell B
(HRB 75) and shall be non-sparking and conductive (see 10.11.5 and 10.15).
The exposed surfaces of the nozzles shall be made of non-sparking materials (see 10.11.5 and 10.15).
5.8 Nozzles shall comply with the performance requirements of Clause 10 to ensure interchangeability.
6 Standard receptacle dimensions
A receptacle shall comply with the design specifications detailed in Figure 1.

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ISO 14469-3:2006(E)
Dimensions in millimetres

NOTES:
Sealing dimensions: ID 9,19 mm ± 0,127 mm; width 2,62 mm ± 0,076 mm.
Sealing surface finish: 0,8 µ ± 0,05 µ.
Material hardness: W HRB 75.
Surface finish range: u 3,2 µ.
a
Minimum length of the receptacle that is clear of provisions for attachment of the receptacle or protective caps.
b
This shaded area shall be kept free of all components.
Figure 1 — Standard receptacle dimensions
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ISO 14469-3:2006(E)
7 Receptacles
7.1 Receptacles shall be evaluated using at least two different test nozzles, each nozzle representing a
different locking technology.
The failure of any test conducted with the receptacle and nozzle test samples shall constitute a failure of the
submitted receptacle, unless the manufacturer can prove the problem was caused by the test nozzle.
7.2 Receptacle designs which employ means on the back diameter as specified in Figure 1 to
accommodate mounting, or for mounting accessories or marking purposes, shall not have such means extend
beyond the back diameter dimensions of the profile as specified in Figure 1, as applicable. Acceptable means
include wrench flats, dust cap anchoring grooves, use of hex stock, undercutting for marking, and threads for
pressure-tight caps. Receptacle designs shall not compromise the interchangeability requirements specified in
Annex C.
7.3 The receptacle shall be equipped with an internal check valve to prevent the escape of gas. The check
valve shall be of the non-contact type, opening by differential pressure only.
7.4 The method for attaching the receptacle to the vehicle fuel system shall not rely on the joint between
the male and female threads for sealing, such as conical threads.
7.5 The interfacing surface of the receptacle shall be constructed of material having a hardness W HRB 75
and shall be non-sparking and conductive (see 10.11.5 and 10.15).
The exposed surfaces of devices shall be made of non-sparking materials (see 10.11.5).
7.6 Receptacles shall have a means to prevent the ingress of fluids and foreign matter.
7.7 The function described in 7.6 may also be met by either a protective cap (see 10.4) or a pressure-tight
protective cap (see 10.16).
7.8 The receptacle shall have provisions to be firmly attached to the vehicle and shall comply with
applicable abnormal load tests (see 10.7).
7.9 The receptacle shall not be installed in an area in which the temperature exceeds 85 °C.
7.10 Receptacles shall have a cycle life > 10 000 cycles.
8 Instructions
This information shall be in a form that is easily understood.
Special tools required for connection of receptacles to tubing and assembly and disassembly of three-way
valve parts shall be clearly identified in the instructions.
Manufacturers of receptacles, nozzles and three-way valves shall provide clear and concise printed
instructions and diagrams in a form that can be easily understood and which are adequate for:
a) proper field assembly;
b) installation;
c) maintenance;
d) replacement of components as appropriate;
e) safe operation by all users;
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ISO 14469-3:2006(E)
f) suitability and use;
g) storage and handling.
9 Marking
This information shall be in a form that is easily understood. Markings shall be embossed, cast, stamped or
otherwise formed on the part in question. This includes markings baked into an enamelled surface.
a) Nozzles and receptacles shall bear the following information:
1) manufacturer's or dealer's name, trademark or symbol;
2) model designation;
3) B250;
4) applicable type and class (see 5.1).
b) Nozzles and receptacles shall each bear a date code marking.
The four-digit date code marking shall consist of at least four adjacent digits determined as follows:
1) the first and second digits shall indicate the calendar year in which the nozzle, receptacle or three-
way valve was manufactured (e.g. 96 for 1996 and 00 for 2000);
2) the third and fourth digits shall indicate the week in which the nozzle, receptacle or three-way valve
was manufactured (e.g. 03 for the third week of the year); for the purpose of this marking, a week
shall begin at 00:01 h on Sunday and end at 24:00 h on Saturday.
A date code may be used for more than one week; however, it shall not be used for more than four
consecutive weeks, or for more than two weeks into the next calendar year.
When a four-digit date code is not practical, the manufacturer shall submit a plan acceptable to the
certifying agency, which will outline means of establishing the date of manufacture so that it is traceable
to the purchaser.
Additional numbers, letters or symbols may follow the four digit number specified in 1) and 2). If additional
numbers are used, they shall be separated from the date code.
c) Marking to identify this part of ISO 14469 shall be provided for each system. This marking may be located
on the package or on a notice placed inside the package in which the device is shipped.
10 Tests
10.1 General requirements
A nozzle and receptacle shall be tested with the receptacle and nozzle designs specified in Clauses 1 to 9.
Unless otherwise stated:
a) tests shall be conducted at room temperature (20 ± 5)°C;
b) all pressure or leak tests shall be conducted with dry air or dry nitrogen;
c) devices shall be conditioned to attain equilibrium conditions.
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ISO 14469-3:2006(E)
Type 2 nozzles shall be tested in series, with either a three-way valve or some other means to independently
pressurize and vent the nozzle. The three-way valve shall not affect temperature, durability or flow
characteristics of the nozzle. Failure of the three-way valve shall not constitute failure of the nozzle. A three-
way valve that is supplied for utilization with a Type 2 nozzle, shall be evaluated separately.
Nozzle tests shall be carried out with the test fixtures, as specified in Annex C, as applicable. A new
receptacle test sample shall be used for each nozzle test. The failure of any test conducted with the nozzle
and receptacle test sample shall constitute a failure of the nozzle design.
10.2 User interface
The appearance of the nozzle and receptacle shall be such as to clearly suggest the proper method of use.
It shall not be possible to deliver gas using Type 1 nozzles unless the nozzle and receptacle are connected
properly and positively locked.
Upon disconnection, Type 1, 2 and 3 nozzles shall stop the flow of gas. No hazardous condition shall result
from disconnection. Type 3 nozzles shall be at 0,7 MPa (7 bar) during this test.
When the contained pressure is less than or equal to 0,7 MPa (7 bar), all nozzles shall be capable of being
disconnected with forces or torques not exceeding 225 N or 7 N⋅m.
The disconnection force/torque shall be applied in a direction that tends to unhook and release the nozzle.
The force/torque shall be applied to the unhooking/release actuator. The torque shall be applied through axis
rotation of the nozzle handle equal to the exterior handling surface of the nozzle uncoupling mechanism and in
a direction such that the nozzle tends to unhook and be released.
On depressurized devices, the axial force to connect and lock or unlock and disconnect the device shall be
u 90 N.
On a positive locking device that incorporates a rotary locking means, the torque needed to lock or unlock the
locking means shall not exceed 1 N⋅m for a device having a diameter u 25,4 mm and 1,7 N⋅m for a device
having a diameter > 25,4 mm.
The minimum force to facilitate disconnection at pressures of 6,25 MPa (62,5 bar) or more, shall be 2,5 × the
force when depressurized (Types 1 and 2) or 0,7 MPa (7 bar) (Type 3). Type 1 nozzles shall be tested with
the vent port plugged.
10.3 Impact resistance
A nozzle shall be connected to a 4,6 m length of 9,5 mm internal diameter (ID) refuelling hose, conditioned at
− 40 °C for 24 h and then dropped 1,8 m on to a concrete floor as shown in Figure 2. The nozzle shall be
dropped ten times, then pressurized to 25 MPa (250 bar) and subjected to ten additional drops. Following
these drops, the nozzle shall be capable of normal connection and disconnection to the receptacle. In addition,
the nozzle shall comply with all leakage tests specified in this part of ISO 14469 (see 10.5).

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ISO 14469-3:2006(E)
Dimensions in metres

Key
1 suitable support
2 refuelling hose (9,5 mm in diameter)
3 concrete floor
4 nozzle
Figure 2 — Impact resistance test arrangement
10.4 Receptacle protective caps
There shall be no permanent distortion or damage to any receptacle protective cap, when tested as follows.
A solid steel ball with a diameter of 50 mm shall be dropped from a height of 300 mm striking the protective
cap installed on the receptacle. The test shall be conducted at − 40 °C and at 85 °C at at least the five points
of impact most likely to cause damage to the receptacle and the protective cap.
10.5 Leakage at room temperature
10.5.1 Nozzle
A nozzle, whether coupled or uncoupled, shall be either bubble-free on the leak test for 1 min or have a leak
3
rate of less than 20 cm /h (normalized) when tested as follows.
Tests shall be conducted at 0,5 MPa (5 bar), 37,5 MPa (375 bar) and then 0,5 MPa (5 bar) again.
Pressurized air or nitrogen shall be applied to the inlet of the coupled (or uncoupled) device. The external
body shall then be checked for bubble-tight leakage using immersion in room temperature water.
All connectors shall be checked for leakage from the time of connection, through full fuel flow, to the time of
disconnection.
If there are no bubbles for a period of 1 min, the sample passes the test. If bubbles are detected then the leak
rate shall be measured by either a vacuum test using helium gas (global accumulation method) or an
equivalent method.
10.5.2 Receptacle
The receptacle check valve shall be either bubble-free on the leak test for 1 min or have a leak rate less than
3
20 cm /h (normalized) when tested as follows.
Tests
...